KR19980015159U - Ultrasonic Vehicle Rear Obstacle Alarm System - Google Patents

Abstract

The present invention relates to a vehicle rear obstacle warning device, and in detail, by detecting the ultrasonic separation distance with the obstacle located in the rear of the vehicle by displaying the number and sound, so that the safe and accurate parking (or stop) It is also possible to simplify the configuration.

Description

Ultrasonic vehicle rear obstacle alarm.

First degree; Circuit block diagram of an embodiment of the present invention.

2nd degree; Detailed circuit diagram of an embodiment of the present invention.

3rd degree; Plan of use of the present invention.

4th degree; Also a time chart of the present invention.

5th; Operation flow chart of the present invention.

* Description of the symbols for the main parts of the drawings *

(US1) (US2)-ultrasonic sensor 20-receiver

30-detector 40-signal comparison

(50) -MICOM (60) -Transmitter

(70)-Oscillator (80)-Reset

(90) -alarm part (100) -display part

110-power supply 120-vehicle

(TL)-Reversing light (B)-Power (battery)

(R1-R56) -resistance (C1-C31) -capacitor

(D1-D15)-Diode (Q1-Q12)-Transistor

(BZ) -Buzzer (SS) -Seven Segment

(IC1) (IC2)-Level Comparison Amplifier (IC3) (IC4)-Constant Voltage IC

(L) -coil (X) -crystal oscillator

(TL) -Reverse light (SW) -Reverse light number position

The present invention relates to a vehicle rear obstacle warning device, and in detail, by detecting the ultrasonic separation distance with the obstacle located in the rear of the vehicle by displaying the number and sound, so that the safe and accurate parking (or stop) It is also possible to simplify the configuration.

In general, since the rear part of the vehicle is relatively large in the blind area, an obstacle alarm is installed at the rear of the vehicle to detect the distance or presence of the obstacle when the vehicle is reversed, and to alert or display it to contribute to safe driving. There are problems such as high failure rate and high price due to complexity.

For example, in the case of a rear obstacle detecting device that installs a camera at the rear of a vehicle and installs a monitor at the front of the driver's seat so that it can drive backward while monitoring the rear of the vehicle, the rear of the vehicle can monitor the rear of the vehicle as a whole but simply transmit images. Subsequently, the distance from the obstacle must be determined based on the rule of thumb, and even then, the distance is difficult to accurately determine the distance, which makes it difficult to park correctly and has a high risk of collision.

In addition, a vehicle object detecting device for detecting an object around a vehicle using ultrasonic waves has been disclosed in Korean Patent Publication No. 94-2098. However, an ultrasonic sensor is used separately for transmitting and receiving, and the overall configuration is complicated, which leads to a failure rate. There were problems such as high price and high price.

Therefore, an object of the present invention is to provide an ultrasonic vehicle rear obstacle warning device having a relatively simple configuration with high operation reliability.

In order to achieve the above object, a transmitter and a reception ultrasonic sensor, a transmitter for oscillating and amplifying ultrasound and supplying the ultrasonic sensor, a double voltage unit for supplying operating power to the transmitter and the transmitted ultrasound are reflected by obstacles. Comparing the reception unit for receiving and amplifying the ultrasonic wave, the detection unit for detecting the received signal, and the detected signal to remove noise components, and comparing the signal comparison unit with the signal input from the signal comparison unit to determine the distance from the obstacle. MICOM which detects and outputs distance display signal and alarm signal, alarm unit that sounds sound when alarm signal is output from micom, distance display unit when distance display signal is output from micom, and micom Connected to the oscillation unit, the reset unit, and the reversing unit, and the power unit to supply the operating power as soon as the vehicle Turning now in detail described with reference to the accompanying drawings, the preferred one kinds of embodiment of the subject innovation as that generated as follows.

FIG. 1 is a block diagram of the present invention, and FIG. 2 is a detailed circuit diagram according to FIG. 1, and an ultrasonic sensor US1 for an ultrasonic transmission / reception, resistors R5 to R12 capacitors C5 and C6 diodes D14. (D15) Transmitter 60, which is composed of transistors Q2 to Q4, voltage-amplifies 40 Hz ultrasonic wave supplied from output terminal RA3 of microcomputer 50 with a large signal and then supplies it to ultrasonic sensor US1. And a voltage divider which is composed of resistors R13 and R14, diodes D4 and D5, capacitors C7 and C8 and transistors Q5 to supply operating power to the transmitter 60, and a circuit. The microcomputer 50 which controls and receives the input signal reflected from the obstacle, obtains the actual distance from the obstacle, and outputs a distance display signal of 0.1m unit and a distance alarm signal of 0.5m, 1.0m, 1.5m unit and Is composed of resistors R15 to R17, zener diode D13, and transistor Q6. A reset unit 80 for initializing the 50 and preventing malfunction, a capacitor C9, C10, and a crystal oscillator X to supply a microcom operating frequency and an ultrasonic wave of about 40 Hz. The alarm unit 90 and the seven segments composed of the oscillation unit 70, the resistors R19, R20, the transistor Q7, and the buzzer BZ are alarmed with a buzzer when an alarm signal is output from the microcomputer 50. Seven segment display (SS) Resistor (R21 to R32) capacitor (C12), display unit (100) consisting of transistors (Q8) and (Q9), resistor (R51), diode (D9), capacitor (C26 to C31), and constant voltage It is composed of IC (IC3) (IC4) and is connected to reverse light (TL), and when shifted to reverse, the power supply unit 110 directly supplied with the operating power source B is connected.

In the above, the microcomputer 50 counts the time at the same time as the ultrasonic transmission and counts the elapsed time until the transmitted ultrasonic wave is reflected by the obstacle and inputs to the receiver, and then obtains the ultrasonic round trip distance by adding the sound velocity. And, by calculating the ultrasonic reciprocating distance to 1/2 to obtain the actual distance between the ultrasonic sensor (US1) and the obstacle, the distance display signal is output when the distance between the obstacle is closer or farther away by 10Cm distance unit The seven segments (SS) allow the distance in 0.1 m units to be displayed numerically.

In addition, an audible alarm is made with a buzzer (BZ) every 0.5m, 1.0m, and 1.5m units, and if the distance from the obstacle is 1.5m or more, the seven segment (SS) displays-,-and the alarm unit (90) ) Is not alarmed, and if the distance to the obstacle is detected to be less than 1.5m from more than 1m, a slow intermittent sound such as beep--beep--bee--is alarmed, and the distance from the obstacle is 0.5m or more. If it detects less than, it will be alerted with a cracking sound of normal speed such as beep, beep, and beep.

In addition, a coupler made of bidirectional diodes D1 and D2 is connected between the signal input / output terminal of the ultrasonic sensor US1 and the transmitter 60 to block noise from entering the receiver 20 during ultrasonic transmission.

In addition, a low noise amplification unit including resistors R1 to R4, capacitors C1 and C2, transistors Q1, and transistor Q1 and protection diode D4 is connected to the signal input / output terminals of the ultrasonic sensor US1. The ultrasonic wave received by US1 is low noise amplified, and the primary amplification unit comprising resistors R33 to R39, capacitors C13 to C17, and transistors Q10, resistors R40 to R42, and capacitors are provided at the output of the low noise amplifier. C19) (C20), transistor Q11, secondary amplifier and detector comprising a detection coil (L) and capacitor (C18) are connected, and resistors (R43 to R50), capacitors (C22) (C23), and diodes ( D7) (D8) and the signal comparator 40 composed of the level comparison amplifiers IC1 and IC2 are connected to remove noise in the received signal and input to the input terminal RAO of the microcomputer 50.

In carrying out the present invention, the ultrasonic sensor can be installed in one or more plural to extend the detection angle (detection range or detection width) or to have a plurality of detection positions, as shown in Figure 2 the receiver 20 and the transmitter An ultrasonic sensor US2, a diode D11 (D12) for preventing noise from entering the receiver during ultrasonic transmission, and resistors R53 to R56 capacitors C24 and C25 transistors Q12. The low noise amplifier may be connected.

In the above, the ultrasonic transmission time is set to be extremely short (250 ㎲ or less) and the receiver is set to about 60 ± 5 ms, so that the ultrasonic transmission and reception can be combined with the single ultrasonic sensor (US1) (US2) without changing the transmission, thus transmitting ultrasonic waves. In this case, the low noise amplification unit, the 1st and 2nd amplification unit, and the detection unit will be amplified and detected as a large signal, but higher than the operating power supply Vcc by the diode D7 connected to the inverting terminal of the level comparison amplifier IC1. Since the signal amplified and detected by the potential is absorbed by the operating power supply Vcc, the level comparison amplifier IC1 and IC2 are protected.

According to the present invention, the ultrasonic sensor US1 US2 is installed at a suitable position in the rear of the vehicle by installing or attaching one ultrasonic sensor US1 to the center of the rear bumper, or the rear bumper. Ultrasonic sensors US1 and US2 are installed on both sides by using a method such as bonding or fastening. When the vehicle 120 is shifted to reverse, the reverse light switch SW is turned on and the left and right reverse lights TL are turned on. It is turned on and power B is supplied to the power supply unit 110 at the same time.

The power supply B supplied to the power supply unit 110 is supplied to the constant voltage ICs IC3 and IC4 through the current limiting resistor R51 and the non-return diode D () to be stabilized and then supplied to each part of the circuit.

The transistor Q6 of the reset unit 80 is turned on by the supply of the power supply Vbb, Vcc, and Vee, and the microcomputer 50 is initialized and operated, and the capacitors C9 and C10 and the crystal oscillator are operated. The MICOM dynamic clock frequency is input to the oscillation terminals OSC1 and OSC2 of the microcomputer 50 through the oscillation unit 70, and part of the clock frequency is 40 kHz by the microcomputer 50. Is output to the output terminal RA3 for the next time between transmitters.

On the other hand, when the ultrasonic transmitter is intermittent, 40 kHz ultrasonic wave is output to the terminal line RA3 of the microcomputer 50 and the elapsed time until the signal input is received after the ultrasonic transmission time is over to the terminal RA0 of the microcomputer 50. The microcomputer 50 recognizes the signal input to the signal input terminal RA0 during the ultrasonic transmitter as a non-reflected unnecessary signal and ignores it.

In addition, when the ultrasonic wave is output to the terminal RA3 of the microcomputer 50, the transistor Q5 of the double voltage unit is switched to 40 kW, and is converted into alternating current, and then composed of a diode D4, D5, and a capacitor C7, C8. Step-up rectification and smoothing by the double-voltage circuit is supplied to the transmitter 60, the transmitter 60 is operated, and the 40 kHz ultrasonic waves outputted to the terminal RA3 are transistors Q2 to Q4 of the transmitter 60. Voltage is amplified by the ultrasonic signal of the large signal and unwanted noise is removed through the coupler diodes D1, D2, D11, and D12, and then supplied to the signal input / output terminals of the ultrasonic sensors US1 and US2.

On the other hand, a part of the ultrasonic waves supplied to the signal input / output terminals of the ultrasonic sensors US1 and US2 during the transmission are resistors R1 to R4 (R53 to R56), capacitors C1 to C2 (C24 to C25), and diode D3. A low noise amplifier consisting of D10 and transistors Q1 and Q2, and amplified by a large signal through the first and second amplification and detection sections, and then detected and input to the comparison amplifier amplifier IC1. The signal amplified by the diode D7 connected to the non-inverting terminal of the comparison amplifier IC1 to a potential higher than the operating power supply Vcc of the level comparison amplifier IC1 (IC2) is absorbed by the operating power supply Vcc and thus is level. Destruction of the comparison amplifiers IC1 and IC2 is prevented.

Meanwhile, the ultrasonic signals input to the ultrasonic sensors US1 and US2 are converted into ultrasonic waves by the ultrasonic sensors US1 and US2 and then diffused and radiated to the rear of the vehicle 120 as a third degree during a short transmission period. The microcomputer 50 continues to count the elapsed time until there is a signal input to the signal input terminal RA0 after switching between receivers.

On the other hand, a part of the ultrasonic waves diffused and radiated to the rear of the vehicle 120 is reflected by an obstacle and received by the ultrasonic sensors US1 and US2 and amplified by the low noise amplifier transistors Q1 and Q12, and then the first and second order. Amplified into a large signal by transistors Q10 and Q11 of the amplifier, detected by coil L, capacitor C18 and transistor Q11, and noise is removed from level comparison amplifier IC1 and IC2. Input to the signal input terminal RA0, the microcomputer 50 acquires the elapsed time from the ultrasonic transmission until there is a signal input to the signal input terminal RA0.

The elapsed time obtained by the microcomputer 50 is the time traveled by the ultrasonic wave, and since it is twice the distance between the ultrasonic sensor US1 and the obstacle, the elapsed time is calculated by 1/2 to obtain a half value, and then the sound velocity [ 331.4m + (0.6 × n ℃)] is added to obtain the actual separation distance L1 between the ultrasonic sensor US1 (US2) and the obstacle, and the display signal output terminals RB0 to RB6 (RA1) (RA2). It outputs a display signal of 0.1m unit through, and the unit distance is displayed numerically by the seven segments (SS) of the display unit 100, the driver can visually easily recognize the separation distance from the obstacle to do safe driving Will be.

On the other hand, if the separation distance from the obstacle (c) is 1.5m or more, the ignore signal is output to the display signal output terminals RB0 to RB6, RA1 and RA2 so that the seven segment SS displays-,-and an alarm. If the distance from the obstacle is greater than 1m and less than 1.5m, the terminal RB7 outputs an alarm signal, so the transistor Q7 is switched at a slow speed so that the buzzer BZ beeps. If the separation distance from the obstacle (B) is closer than 0.5m and less than 1m, the transistor Q7 is switched at the normal speed to beep-pi-pi-, and the obstacle When the separation distance is even closer to less than 0.5m, the transistor (Q7) is switched at a high speed to alarm the beep, so that the driver can easily recognize the degree of approach to the obstacle and can drive safely.

Meanwhile, since the magnitude of the signal input to the non-inverting signal input terminal of the level comparison amplifier IC1 is proportional to the proximity of the obstacle, the reference voltage input to the inverting terminal of the level comparison amplifier IC1 needs to be proportionally changed. The signal compared by the jumper wire connecting the inverting terminal and the output terminal of the bar level comparison amplifier IC1 is fed back to the inverting terminal and charged and discharged by the capacitor C22, so that the reference voltage is applied to the level of the input signal. The noise is removed by comparing with the reference signal supplied to the non-inverting terminal of the other level comparison amplifier IC2. The signal is input to the signal input terminal RA0 of the microcomputer and the diode D8 is connected to the level comparison amplifier IC2. Only the high signal is input to the diode (D10) (D15) to protect the transistor (Q3) (Q12) by preventing the negative voltage (-).

In the present invention, if there is a signal input as a signal input terminal of the microcomputer 50 between the ultrasonic transmitters, it is ignored so that the USUS (US2) can be used for both transmission and reception. It can reduce the effect.

Claims (1)

In the ultrasonic vehicle rear obstacle warning device, the transmitter 60 for amplifying and supplying the ultrasonic sensor US1 (US2) and the ultrasonic wave supplied from the microcomputer to the ultrasonic sensor US1 (US2) and the transmitted ultrasonic wave Receiving unit 20 for receiving and then amplifying the ultrasonic waves reflected by the obstacle to the ultrasonic sensor (US1) (US2), the detector 30 for detecting the received signal, and the detected signal compared to the reference signal noise The signal comparator 40 which removes the component and the elapsed time until the transmitted ultrasonic wave is reflected by the obstacle and input to the signal comparator 40 are obtained to obtain the distance from the obstacle, and then the distance display signal and the alarm A microcomputer 50 for outputting a signal and controlling transmission and reception, a display unit 100 for displaying a distance when a distance display signal is output from the microcomputer 50, and a sound when an alarm signal is output from the microcomputer 50. Alarm unit to be alerted (90) The reset unit 80 for initializing the microcomputer 50, the oscillation unit 70 for acquiring the clock frequency and the ultrasonic oscillation frequency of the microcomputer 50, and the operating power is supplied when the reverse light TL of the vehicle is turned on. Ultrasonic vehicle rear obstacle warning device composed of a power supply unit 110.